Communication and Perception

Cebid species are very vocal, with a wide variety of social and alarm calls. Capuchin species are reported to have alarm calls that vary in frequency and duration to indicate the relative distance of harpy eagles. Cebid species have calls that indicate distance to maintain social cohesion, alert other group members of the presence of predators, and vocalizations to elicit specific responses in other group members, such as food soliciting in young. Vocalizations seem to be learned, as young cebids "babble" and don't show proper contextual use of vocalizations.

Cebid species also extensively use chemical cues in communication. Squirrel monkeys and capuchins practice urine washing of their fur, possibly in order to scent mark the environment. Marmosets and tamarins apply scent gland secretions to objects in their environment as well as other members of their social group, urine washing has been observed rarely. Scent marking "parties" have been reported in mustached tamarins, where multiple individuals get together to scent mark each other and objects for several minutes. Scent marking may be more frequent in males or females, depending on social organization. Capuchins also practice self-anointment, where they rub their bodies with an odiferous substance.

Visual displays are also used, such as the genital displays of squirrel monkeys. Genital displays are used as a greeting and as a way to exert dominance. Posturing, facial expressions, and the fluffing of fur and hairy tufts are other forms of visual communication.

Cebid species are highly visual animals, using their keen eyesight and binocular vision to navigate their environment, find food, and avoid predation.